[Objective] This study was to provide basis for the scientific management of land use in Haihe River Basin (HRB) through the quantitative exploration of the land use conversion, changes of intensity and spatial dist...[Objective] This study was to provide basis for the scientific management of land use in Haihe River Basin (HRB) through the quantitative exploration of the land use conversion, changes of intensity and spatial distribution in this region. [Method] With the support of remote sensing technology and geographic information technology, the land use maps of the study area in 40 years (1970-2010) were in- terpreted and plotted. Four kinds of tupu, namely, land use change tupu, process tupu, arising tupu and evolution mode tupu were built through the spatial overlay of the land use maps to analyze the change rules of land use patterns. [Result] The conversion of arable land to construction land was the main characteristics of land use changes in HRB for the 40 years; the area of non-stable region accounted for 35% of the total, indicating that the land use changed remarkably, thus, it was nec- essary to strengthen the scientific land management in HRB; the new conversions to all land use patterns were all the lowest in 1980-1990, indicating that land use changed slowly during this period. [Conclusion] The results indicate that, compared with conventional transfer matrix method, geo-information tupu has obvious advantage in analyzing land use changes that it can demonstrate the spatial distribution of interest region, display the multi-dimensional spatial information.展开更多
The effects of socio-demographics, land use characteristics and trip attributes on the commute mode choice are studied with a nested logit (NL) model. Based on the random utility maximum theory, the NL model is form...The effects of socio-demographics, land use characteristics and trip attributes on the commute mode choice are studied with a nested logit (NL) model. Based on the random utility maximum theory, the NL model is formulated. The analysis is carried out in the main area of Nanjing. Direct and cross elasticities are calculated to analyze the effects of travel time and travel cost on the selection of travel mode choice. The results reveal that the non-motorized travel modes are more attractive in the areas with higher housing and employment accessibility and car owners are found to be more likely to commute to work by car. The bus and subway choice probabilities are more sensitive to changes in travel times than to changes in travel costs. In conclusion, a comprehensive public transit system and effective integration of land use and transportation policies help to relieve the traffic congestion levels caused by the increasing urban sprawl.展开更多
Human activities alter land use patterns and affect landscape sustainability. It is therefore very important to investigate the relationship between land use change and human activities. This study focuses on the dete...Human activities alter land use patterns and affect landscape sustainability. It is therefore very important to investigate the relationship between land use change and human activities. This study focuses on the detection of changing land use patterns in the Yanhe River Basin in northern Loess Plateau of China between 1995 and 2008. Landscape metrics were used to analyze the changing land use patterns and to explore the related anthropogenic driving forces. Results show that:1) Totally, 186 590 ha of croplands were converted into alternate land-use types (equivalent to 61.7% of the original cropland area). The majority of cropland areas were found to be converted into grassland and woodland areas (accounting for 55.9% and 4.9% respectively of the original cropland areas). 2) Both cropland and woodland demonstrated an increasing fragmentation tendency while grasslands showed a decreasing fragmentation tendency. 3) Multiple driving forces of land use change were thought to act together to changes in landscape metrics in the Yanhe River Basin. The anthropogenic driving forces were analyzed from four perspectives:ecological conservation policy, labor force transfer, industrial development, and rural settlement. The policy of the GfG (Grain for Green) project was the main driving factor which expedited the conversion from cropland to woodland and grassland. Industrial development was also found to affect land use change through the direct impact of economic activities such as oil exploration and agricultural production, or through indirect impacts such as the industrial structures readjustment. Labor force transfer from rural to urban areas was found to follow the industrial structure readjustment and further drove land use change from cropland to off-farm land use. Establishment of new tile-roofed houses instead of cave-type dwellings in rural settlements has helped to aggregate the original scattered land-use type of construction.展开更多
Land scarcity has become the prominent obstacle on the way to sustainable development for China. Under the constraints of land shortage, how to allocate the finite land resources to the multiple land users in China co...Land scarcity has become the prominent obstacle on the way to sustainable development for China. Under the constraints of land shortage, how to allocate the finite land resources to the multiple land users in China considering various political, environmental, ecological and economic conditions have become research topics with great significance. In this study, an interval fuzzy national-scale land-use model(IFNLM) was developed for optimizing land systems of China. IFNLM is based on an integration of existing interval linear programming(ILP), and fuzzy flexible programming(FFP) techniques. IFNLM allows uncertainties expressed as discrete interval values and fuzzy sets to be incorporated within a general optimization framework. It can also facilitate national-scale land-use planning under various environmental, ecological, social conditions within a multi-period and multi-option context. Then, IFNLM was applied to a real case study of land-use planning in China. The satisfaction degree of environmental constraints is between 0.69 and 0.97, the system benefit will between 198.25 × 1012 USD and 229.67 × 1012 USD. The results indicated that the hybrid model can help generate desired policies for land-use allocation with a maximized economic benefit and minimized environmental violation risk. Optimized land-use allocation patterns can be generated from the proposed IFNLM.展开更多
Although extensive analyses of road segments and intersections located in urban road networks have examined the role of many factors that contribute to the frequency and severity of crashes, the explicit relationship ...Although extensive analyses of road segments and intersections located in urban road networks have examined the role of many factors that contribute to the frequency and severity of crashes, the explicit relationship between street pattern characteristics and traffic safety remains underexplored. Based on a zone-based Hong Kong database, the Space Syntax was used to quantify the topological characteristics of street patterns and investigate the role of street patterns and zone-related factors in zone-based traffic safety analysis. A joint probability model was adopted to analyze crash frequency and severity in an integrated modeling framework and the maximum likelihood estimation method was used to estimate the parameters. In addition to the characteristics of street patterns, speed, road geometry, land-use patterns, and temporal factors were considered. The vehicle hours was also included as an exposure proxy in the model to make crash frequency predictions. The results indicate that the joint probability model can reveal the relationship between zone-based traffic safety and various other factors, and that street pattern characteristics play an important role in crash frequency prediction.展开更多
Taking Guangzhou as a case,this paper adopted a questionnaire survey to gather first-hand data and analyzed the characteristics and influencing factors of private car travel in Chinese cities.As the research indicated...Taking Guangzhou as a case,this paper adopted a questionnaire survey to gather first-hand data and analyzed the characteristics and influencing factors of private car travel in Chinese cities.As the research indicated,trip purposes of private car travel are mainly commute and business affairs with a more flexible trip in the urban core area.And trip intensities are concentrated in a certain extent,with trip frequency being lower in the urban core area than the peripheral area.In addition,the trip time has two significant peaks occurring in the morning and afternoon,and one trough in the midday.And trip spatial distribution is mainly within commute with both residence and employment in urban area and inward commute with residence in suburban area while employment in urban area.Both kinds of commutes direct to the urban area.The study also shows that the characteristics of private car travel are principally influenced by two aspects:travelers' attributes and urban characteristics.The main travelers' social and economic attributes influenced it include the gender,education attainment,age,driving experience and per capita monthly household income.The urban characteristics influenced it mainly cover the land use pattern,public traffic facilities and spatial attributes of residential environment.展开更多
There are about 1.27 million ha of upland red soils derived from Quaternary red clay facing the degradation in the low-hilly region of the middle subtropical China. From the aspects of chemistry, physics and microbiol...There are about 1.27 million ha of upland red soils derived from Quaternary red clay facing the degradation in the low-hilly region of the middle subtropical China. From the aspects of chemistry, physics and microbiology, the processes of soil fertility restoration in the surface layer (0~20 cm) under three types of land use patterns (i.e. citrus orchard, tea garden and upland) in two provinces were studied in this work. Results showed that the reclamation of eroded waste land improved most of soil properties. Soil organic matter, total N and P, available P and K, and exchangeable Ca and Mg increased, but soil total K and exchangeable Al decreased. Soil PH decreased by 0.5 unit in the pure tea plantation for 20 years. Soil reclamation increased the percentage of soil microaggregates (<0.25 mm), especially those with a diameter of 0.02~0.002 mm. Soil total porosity increased in the cultivated lands with the increase of soil aeration and capillary porosity. The number of soil microorganisms increased with reclamation caused mainly by the huge increase of the total amount of bacteria. With the cultivation, the activity of soil urease and acid phosphatase increased, but that of invertase dropped.展开更多
The agro-pastoral ecotone has been recognized as the main distribution area of reserved land resource for cultivation. Accordingly, clarifying this assumption, as well as concerting land reclamation and ecological res...The agro-pastoral ecotone has been recognized as the main distribution area of reserved land resource for cultivation. Accordingly, clarifying this assumption, as well as concerting land reclamation and ecological restoration, is important to ensure food security and environmental improvement in the agro-pastoral ecotone. We selected Horqin Left Back Banner(HLBB) as the subject of our case study. The landscape ecological security pattern of this area was determined using the minimum cumulative resistance model. Over-cultivation, quantity of reserved land resource for cultivation, and changes in landscape indexes before and after land use adjustment were then analyzed. Over-cultivation is a serious problem in the agro-pastoral ecotone. Reserved land resource for cultivation is less than that considered previously, and the area of reserved land resource for cultivation in HLBB only accounts for 11.50% of total uncultivated land. With regard to changes in landscape indexes, the adjusted land use pattern is effective for anti-desertification. The compensation standard for abandoned cultivated land should be improved and the comprehensive results of ‘Grain for Green' should be evaluated to further implement ecological restoration in the agro-pastoral ecotone.展开更多
Land use/cover change (LUCC) is a key aspect of global environment change, and in a sense indicates the influence of human activities on natural environment. Regional case study is the core of LUCC research. Taking th...Land use/cover change (LUCC) is a key aspect of global environment change, and in a sense indicates the influence of human activities on natural environment. Regional case study is the core of LUCC research. Taking the southern Liaoning Province, a coastal area facing the Bohai Sea and the Huanghai Sea, as an example, supported by ARCVIEW and ARC/INFO, this paper reconstructed LUCC patterns in three periods of 1954, 1976 and 2000, and analyzed their spatial-temporal changes from 1954 to 2000. On the base of these, it also studied the LUCC’s driving mechanism. The results show that the land transformation mainly occurs among cultivated land, forestland and urban and industrial land. Industrialization and urbanization in rural area are the major driving forces for cultivated land change, and the extension of the built-up area in cities is mainly the result of economic development and tertiary industry development, etc., which is at expense of cultivated land.展开更多
This investigation is an analysis of the influence of landform instability on the distribution of land-use dynamics in a hydrographical basin, located in the Mexican Volcanic Belt mountain range (central Mexico), curr...This investigation is an analysis of the influence of landform instability on the distribution of land-use dynamics in a hydrographical basin, located in the Mexican Volcanic Belt mountain range (central Mexico), currently affected by substantial changes in land use and deforestation. A landform map was produced, in addition to seven attribute maps - altimetry, drainage density, slope, relief energy, potential erosion, geology and tectonics - which were considered as factors for determining landform instability through Multi-criteria Evaluation Analysis. Likewise, the direction and rhythm of land-use dynamics were analyzed in four dates - between 1976 and 2000 - and cross tabulations were made between them, in order to analyze the trends and processes of land-use dynamics. Afterwards, the databases obtained were cross tabulated with the landform variables to derive areas, percentages and correlation indices. In the study area, high-instability landforms are associated with most ancient volcanic and sedimentary landforms, where high altitude, drainage density, slope and potential to develop gravitational and fluvial processes are the major factors favouring a land-use pattern, dominated by the conservation of extensive forest land, abandonment of human land use and regeneration of disturbed areas. In contrast, low-instability landforms correspond to alluvial plains and lava hills covered by pyroclasts, where low potential erosion to develop fluvial processes, added to water and soil availability and accessibility, have favoured a land-use pattern dominated by the expansion of agroforestry plantations and human settlements, showing a marked trend towards either intensification or permanence of the current land use and with little abandonment and regeneration.展开更多
This study investigated and simulated land use patterns in Beijing for the year 2000 and the year 2005 from the actual land use data for the year 1995 and the year 2000,respectively,by combining spatial land allocatio...This study investigated and simulated land use patterns in Beijing for the year 2000 and the year 2005 from the actual land use data for the year 1995 and the year 2000,respectively,by combining spatial land allocation simulation using the CLUE-S model,and numerical land demand prediction using the Markov model.The simulations for 2000 and 2005 were confirmed to be generally accurate using Kappa indices.Then the land-use scenarios for Beijing in 2015 were simulated assuming two modes of development:1) urban development following existing trends;and 2) under a strict farmland control.The simulations suggested that under either mode,urbanized areas would expand at the expense of land for other uses.This expansion was predicted to dominate the land-use conversions between 2005 and 2015,and was expected to be accompanied by an extensive loss of farmland.The key susceptible to land-use changes were found to be located at the central urban Beijing and the surrounding regions including Yanqing County,Changping District and Fangshan District.Also,the simulations predicted a considerable expansion of urban/suburban areas in the mountainous regions of Beijing,suggesting a need for priority monitoring and protection.展开更多
The research objective was to investigate past and current forest management practices in the Maluku archipelago, then to create a better management model to improve prosperity for local communities and to guarantee s...The research objective was to investigate past and current forest management practices in the Maluku archipelago, then to create a better management model to improve prosperity for local communities and to guarantee sustainability of forest ecosystems for future generations. Forest land use, the deforestation process, the potential for maintaining natural production forests and the need to establish a management unit for sustainability of natural production forests (PFMU) were analysed. The analysis model used Geographic Information System (GIS) and satellite imaging. The deforestation process was analysed using the multiple regression model. The research determined the importance of two concepts i.e., (1) A macro concept involving the integration of forest development with regional development and (2) A micro concept which detailed the format of the PFMU as a sub-set of the macro concept. The macro concept involves a new Forest Land Use Plan (FLUP), and the micro concept is a more detailed analysis of a sustainable PFMU, a Management Unit for Protection Forest (PrFMU) and a Management Unit for Conservation Forest (CFMU). Results showed that the existing FLUCP (Forest Land Use Consensus Plan) policy rather than guaranteeing the sustainability of forests, contributed to their deforestation. The integration of forest management and regional development strategies required the establishment of a new FLUP.展开更多
Land-use patterns can affect various nutrient cycles in stream ecosystems, but little information is available about the effects of urban development on denitrification processes at the watershed scale. In the present...Land-use patterns can affect various nutrient cycles in stream ecosystems, but little information is available about the effects of urban development on denitrification processes at the watershed scale. In the presented study, we investigated the controlling factors of denitrification rates within the streams of the Han River Basin, Korea, with different land-use patterns, in order to enhance the effectiveness of water resource management strategies. Ten watersheds were classified into three land-use patterns (forest, agriculture and urban) using satellite images and geographic information system techniques, and in-situ denitrification rates were determined using an acetylene blocking method. Additionally, sediment samples were collected from each stream to analyze denitrifier communities and abundance using molecular approaches. In-situ denitrification rates were found to be in the order of agricultural streams (289.6 mg N20-N m-2 d-1) 〉 urban streams (157.0 mg N20-N m-2 d-1) 〉 forested streams (41.9 mg N20-N m-2 d-l). In contrast, the average quantity of denitrifying genes was the lowest in the urban streams. Genetic diversity of denitrifying genes was not affected by watershed land-use pattern, but exhibited stream-dependent pattern. More significance factors were involved in denitrification in the sites with higher denitrification rates. Multiple linear regression analysis revealed that clay, dissolved organic carbon and water contents were the main factors controlling denitrification rate in the agricultural streams, while dissolved organic carbon was the main controlling factor in the urban streams. In contrast, temperature appeared to be the main controlling factor in the forested streams.展开更多
Reducing Emissions from Deforestation and Forest Degradation(REDD+) and enhancing "removals of greenhouse gas emissions by forests" in developing countries through positive incentives is regarded as an essen...Reducing Emissions from Deforestation and Forest Degradation(REDD+) and enhancing "removals of greenhouse gas emissions by forests" in developing countries through positive incentives is regarded as an essential component of the post-2012 climate regime for stabilizing greenhouse gas emissions and an important way of engaging developing countries in global mitigation efforts. We aimed to evaluate the potential effectiveness of REDD+ by integrating it into a land use option framework. One of our goals was to develop scenarios for evaluating the impacts of land use changes on carbon and environmental processes. In addition, we aimed to quantify the potential economic benefits to society of compensated reductions and to identify hotspots for applying REDD+. Three land use change scenarios were examined:(I) business as usual(BAU),(II) economic development, and(III) REDD+. A case study in Indonesia was examined using these land use scenarios and policy interventions, evaluating their effects on carbon emissions, socioeconomics, and environmental features of a spatial system using land use models. Significant emissions and water erosion reductions were predicted to be achieved under the REDD+ scenario, due to reduced deforestation of <6% over the next decade; >0.14 Mt CO2 e reduction was predicted relative to the BAU scenario. Furthermore, the spatial land use model indicated that REDD+ payments of forest carbon credits in the compliance market would play a key role in compensating rural communities and plantation companies for their opportunity cost in ending deforestation. This study provides an example of integrating land use modeling with a scenario analysis framework to evaluate plausible future forecasts and to evaluate the potential impacts of REDD+.展开更多
Land use and land cover change(LUCC)is one of the important human forcing on climate.However,it is difficult to infer how LUCC will affect climate in the future from the effects of previous LUCC on regional climates i...Land use and land cover change(LUCC)is one of the important human forcing on climate.However,it is difficult to infer how LUCC will affect climate in the future from the effects of previous LUCC on regional climates in the past.Thus,based on the land cover data recommended by the Coupled Model Intercomparison Project Phase 5(CMIP5),a regional climate model(Reg CM4)was used to investigate the climate effects of future land use change over China.Two 15-year simulations(2036–2050),one with the current land use data and the other with future land cover scenario(2050)were conducted.It is noted that future LUCC in China is mainly characterized by the transition from the grassland to the forest.Results suggest that the magnitudes and ranges of the changes in temperature and precipitation caused by future LUCC show evident seasonality,which are more prominent in summer and autumn.Significant response of climate to future LUCC mainly happens in Northeast China,North China,the Hetao Area,Eastern Qinghai-Tibetan Plateau and South China.Further investigation shows that future LUCC can also produce significant impacts on the atmospheric circulation.LUCC results in abnormal southwesterly wind over extensive areas from the Indian peninsula to the coasts of the South China Sea and South China through the Bay of Bengal.Furthermore,Indian tropical southwest monsoons and South Sea southwest monsoons will both be strong,and the abnormal water vapor convergence from the South China Sea and the Indian Ocean will result in more precipitation in South China.展开更多
基金Supported by the Key Technology R&D Program of Hebei Province (10277105D)the Funds of the Chinese Academy of Sciences for Key Topics in Innovation Engineering(KSCX-EW-J-5)~~
文摘[Objective] This study was to provide basis for the scientific management of land use in Haihe River Basin (HRB) through the quantitative exploration of the land use conversion, changes of intensity and spatial distribution in this region. [Method] With the support of remote sensing technology and geographic information technology, the land use maps of the study area in 40 years (1970-2010) were in- terpreted and plotted. Four kinds of tupu, namely, land use change tupu, process tupu, arising tupu and evolution mode tupu were built through the spatial overlay of the land use maps to analyze the change rules of land use patterns. [Result] The conversion of arable land to construction land was the main characteristics of land use changes in HRB for the 40 years; the area of non-stable region accounted for 35% of the total, indicating that the land use changed remarkably, thus, it was nec- essary to strengthen the scientific land management in HRB; the new conversions to all land use patterns were all the lowest in 1980-1990, indicating that land use changed slowly during this period. [Conclusion] The results indicate that, compared with conventional transfer matrix method, geo-information tupu has obvious advantage in analyzing land use changes that it can demonstrate the spatial distribution of interest region, display the multi-dimensional spatial information.
基金The National Natural Science Foundation of China(No.50908051)
文摘The effects of socio-demographics, land use characteristics and trip attributes on the commute mode choice are studied with a nested logit (NL) model. Based on the random utility maximum theory, the NL model is formulated. The analysis is carried out in the main area of Nanjing. Direct and cross elasticities are calculated to analyze the effects of travel time and travel cost on the selection of travel mode choice. The results reveal that the non-motorized travel modes are more attractive in the areas with higher housing and employment accessibility and car owners are found to be more likely to commute to work by car. The bus and subway choice probabilities are more sensitive to changes in travel times than to changes in travel costs. In conclusion, a comprehensive public transit system and effective integration of land use and transportation policies help to relieve the traffic congestion levels caused by the increasing urban sprawl.
基金Under the auspices of National Natural Science Foundation of China(No.40930528)State Forestry Administration of China(No.201004058)External Cooperation Program of Chinese Academy of Sciences(No.29GJHZ0948)
文摘Human activities alter land use patterns and affect landscape sustainability. It is therefore very important to investigate the relationship between land use change and human activities. This study focuses on the detection of changing land use patterns in the Yanhe River Basin in northern Loess Plateau of China between 1995 and 2008. Landscape metrics were used to analyze the changing land use patterns and to explore the related anthropogenic driving forces. Results show that:1) Totally, 186 590 ha of croplands were converted into alternate land-use types (equivalent to 61.7% of the original cropland area). The majority of cropland areas were found to be converted into grassland and woodland areas (accounting for 55.9% and 4.9% respectively of the original cropland areas). 2) Both cropland and woodland demonstrated an increasing fragmentation tendency while grasslands showed a decreasing fragmentation tendency. 3) Multiple driving forces of land use change were thought to act together to changes in landscape metrics in the Yanhe River Basin. The anthropogenic driving forces were analyzed from four perspectives:ecological conservation policy, labor force transfer, industrial development, and rural settlement. The policy of the GfG (Grain for Green) project was the main driving factor which expedited the conversion from cropland to woodland and grassland. Industrial development was also found to affect land use change through the direct impact of economic activities such as oil exploration and agricultural production, or through indirect impacts such as the industrial structures readjustment. Labor force transfer from rural to urban areas was found to follow the industrial structure readjustment and further drove land use change from cropland to off-farm land use. Establishment of new tile-roofed houses instead of cave-type dwellings in rural settlements has helped to aggregate the original scattered land-use type of construction.
基金Under the auspices of National Natural Science Foundation of China(No.41201164)Humanities and Social Science Research Planning Fund,Ministry of Education of China(No.12YJCZH299)
文摘Land scarcity has become the prominent obstacle on the way to sustainable development for China. Under the constraints of land shortage, how to allocate the finite land resources to the multiple land users in China considering various political, environmental, ecological and economic conditions have become research topics with great significance. In this study, an interval fuzzy national-scale land-use model(IFNLM) was developed for optimizing land systems of China. IFNLM is based on an integration of existing interval linear programming(ILP), and fuzzy flexible programming(FFP) techniques. IFNLM allows uncertainties expressed as discrete interval values and fuzzy sets to be incorporated within a general optimization framework. It can also facilitate national-scale land-use planning under various environmental, ecological, social conditions within a multi-period and multi-option context. Then, IFNLM was applied to a real case study of land-use planning in China. The satisfaction degree of environmental constraints is between 0.69 and 0.97, the system benefit will between 198.25 × 1012 USD and 229.67 × 1012 USD. The results indicated that the hybrid model can help generate desired policies for land-use allocation with a maximized economic benefit and minimized environmental violation risk. Optimized land-use allocation patterns can be generated from the proposed IFNLM.
基金Project(71301083)supported by the National Natural Science Foundation of ChinaProject(2012AA112305)supported by the National High-Tech Research and Development Program of China+1 种基金Project(2012CB725405)supported by the National Basic Research Program of ChinaProject(17208614)supported by the Research Grants Council of the Hong Kong Special Administrative Region,China
文摘Although extensive analyses of road segments and intersections located in urban road networks have examined the role of many factors that contribute to the frequency and severity of crashes, the explicit relationship between street pattern characteristics and traffic safety remains underexplored. Based on a zone-based Hong Kong database, the Space Syntax was used to quantify the topological characteristics of street patterns and investigate the role of street patterns and zone-related factors in zone-based traffic safety analysis. A joint probability model was adopted to analyze crash frequency and severity in an integrated modeling framework and the maximum likelihood estimation method was used to estimate the parameters. In addition to the characteristics of street patterns, speed, road geometry, land-use patterns, and temporal factors were considered. The vehicle hours was also included as an exposure proxy in the model to make crash frequency predictions. The results indicate that the joint probability model can reveal the relationship between zone-based traffic safety and various other factors, and that street pattern characteristics play an important role in crash frequency prediction.
基金Under the auspices of National Natural Science Foundation of China (No 40571052,40301014)
文摘Taking Guangzhou as a case,this paper adopted a questionnaire survey to gather first-hand data and analyzed the characteristics and influencing factors of private car travel in Chinese cities.As the research indicated,trip purposes of private car travel are mainly commute and business affairs with a more flexible trip in the urban core area.And trip intensities are concentrated in a certain extent,with trip frequency being lower in the urban core area than the peripheral area.In addition,the trip time has two significant peaks occurring in the morning and afternoon,and one trough in the midday.And trip spatial distribution is mainly within commute with both residence and employment in urban area and inward commute with residence in suburban area while employment in urban area.Both kinds of commutes direct to the urban area.The study also shows that the characteristics of private car travel are principally influenced by two aspects:travelers' attributes and urban characteristics.The main travelers' social and economic attributes influenced it include the gender,education attainment,age,driving experience and per capita monthly household income.The urban characteristics influenced it mainly cover the land use pattern,public traffic facilities and spatial attributes of residential environment.
文摘There are about 1.27 million ha of upland red soils derived from Quaternary red clay facing the degradation in the low-hilly region of the middle subtropical China. From the aspects of chemistry, physics and microbiology, the processes of soil fertility restoration in the surface layer (0~20 cm) under three types of land use patterns (i.e. citrus orchard, tea garden and upland) in two provinces were studied in this work. Results showed that the reclamation of eroded waste land improved most of soil properties. Soil organic matter, total N and P, available P and K, and exchangeable Ca and Mg increased, but soil total K and exchangeable Al decreased. Soil PH decreased by 0.5 unit in the pure tea plantation for 20 years. Soil reclamation increased the percentage of soil microaggregates (<0.25 mm), especially those with a diameter of 0.02~0.002 mm. Soil total porosity increased in the cultivated lands with the increase of soil aeration and capillary porosity. The number of soil microorganisms increased with reclamation caused mainly by the huge increase of the total amount of bacteria. With the cultivation, the activity of soil urease and acid phosphatase increased, but that of invertase dropped.
基金Foundation item:Under the auspices of the Special Scientific Research of the Ministry of Land and Resources of China(No.201411009)
文摘The agro-pastoral ecotone has been recognized as the main distribution area of reserved land resource for cultivation. Accordingly, clarifying this assumption, as well as concerting land reclamation and ecological restoration, is important to ensure food security and environmental improvement in the agro-pastoral ecotone. We selected Horqin Left Back Banner(HLBB) as the subject of our case study. The landscape ecological security pattern of this area was determined using the minimum cumulative resistance model. Over-cultivation, quantity of reserved land resource for cultivation, and changes in landscape indexes before and after land use adjustment were then analyzed. Over-cultivation is a serious problem in the agro-pastoral ecotone. Reserved land resource for cultivation is less than that considered previously, and the area of reserved land resource for cultivation in HLBB only accounts for 11.50% of total uncultivated land. With regard to changes in landscape indexes, the adjusted land use pattern is effective for anti-desertification. The compensation standard for abandoned cultivated land should be improved and the comprehensive results of ‘Grain for Green' should be evaluated to further implement ecological restoration in the agro-pastoral ecotone.
基金Under theauspices of Chinese Academy of Sciences(No .KZCX2-SW-320 )
文摘Land use/cover change (LUCC) is a key aspect of global environment change, and in a sense indicates the influence of human activities on natural environment. Regional case study is the core of LUCC research. Taking the southern Liaoning Province, a coastal area facing the Bohai Sea and the Huanghai Sea, as an example, supported by ARCVIEW and ARC/INFO, this paper reconstructed LUCC patterns in three periods of 1954, 1976 and 2000, and analyzed their spatial-temporal changes from 1954 to 2000. On the base of these, it also studied the LUCC’s driving mechanism. The results show that the land transformation mainly occurs among cultivated land, forestland and urban and industrial land. Industrialization and urbanization in rural area are the major driving forces for cultivated land change, and the extension of the built-up area in cities is mainly the result of economic development and tertiary industry development, etc., which is at expense of cultivated land.
基金the National Autonomous University of Mexico, under project DGAPA-PAPIIT number IN-300911-3
文摘This investigation is an analysis of the influence of landform instability on the distribution of land-use dynamics in a hydrographical basin, located in the Mexican Volcanic Belt mountain range (central Mexico), currently affected by substantial changes in land use and deforestation. A landform map was produced, in addition to seven attribute maps - altimetry, drainage density, slope, relief energy, potential erosion, geology and tectonics - which were considered as factors for determining landform instability through Multi-criteria Evaluation Analysis. Likewise, the direction and rhythm of land-use dynamics were analyzed in four dates - between 1976 and 2000 - and cross tabulations were made between them, in order to analyze the trends and processes of land-use dynamics. Afterwards, the databases obtained were cross tabulated with the landform variables to derive areas, percentages and correlation indices. In the study area, high-instability landforms are associated with most ancient volcanic and sedimentary landforms, where high altitude, drainage density, slope and potential to develop gravitational and fluvial processes are the major factors favouring a land-use pattern, dominated by the conservation of extensive forest land, abandonment of human land use and regeneration of disturbed areas. In contrast, low-instability landforms correspond to alluvial plains and lava hills covered by pyroclasts, where low potential erosion to develop fluvial processes, added to water and soil availability and accessibility, have favoured a land-use pattern dominated by the expansion of agroforestry plantations and human settlements, showing a marked trend towards either intensification or permanence of the current land use and with little abandonment and regeneration.
基金Under the auspices of National Natural Science Foundation of China (No. 70903061,41171440)National Public Benefit (Land) Research Foundation of China (No. 201111014)Fundamental Research Funds for the Central Universities (No. 2011YXL055)
文摘This study investigated and simulated land use patterns in Beijing for the year 2000 and the year 2005 from the actual land use data for the year 1995 and the year 2000,respectively,by combining spatial land allocation simulation using the CLUE-S model,and numerical land demand prediction using the Markov model.The simulations for 2000 and 2005 were confirmed to be generally accurate using Kappa indices.Then the land-use scenarios for Beijing in 2015 were simulated assuming two modes of development:1) urban development following existing trends;and 2) under a strict farmland control.The simulations suggested that under either mode,urbanized areas would expand at the expense of land for other uses.This expansion was predicted to dominate the land-use conversions between 2005 and 2015,and was expected to be accompanied by an extensive loss of farmland.The key susceptible to land-use changes were found to be located at the central urban Beijing and the surrounding regions including Yanqing County,Changping District and Fangshan District.Also,the simulations predicted a considerable expansion of urban/suburban areas in the mountainous regions of Beijing,suggesting a need for priority monitoring and protection.
文摘The research objective was to investigate past and current forest management practices in the Maluku archipelago, then to create a better management model to improve prosperity for local communities and to guarantee sustainability of forest ecosystems for future generations. Forest land use, the deforestation process, the potential for maintaining natural production forests and the need to establish a management unit for sustainability of natural production forests (PFMU) were analysed. The analysis model used Geographic Information System (GIS) and satellite imaging. The deforestation process was analysed using the multiple regression model. The research determined the importance of two concepts i.e., (1) A macro concept involving the integration of forest development with regional development and (2) A micro concept which detailed the format of the PFMU as a sub-set of the macro concept. The macro concept involves a new Forest Land Use Plan (FLUP), and the micro concept is a more detailed analysis of a sustainable PFMU, a Management Unit for Protection Forest (PrFMU) and a Management Unit for Conservation Forest (CFMU). Results showed that the existing FLUCP (Forest Land Use Consensus Plan) policy rather than guaranteeing the sustainability of forests, contributed to their deforestation. The integration of forest management and regional development strategies required the establishment of a new FLUP.
基金Supported by the National Research Foundation of Korea(No.2013056833)
文摘Land-use patterns can affect various nutrient cycles in stream ecosystems, but little information is available about the effects of urban development on denitrification processes at the watershed scale. In the presented study, we investigated the controlling factors of denitrification rates within the streams of the Han River Basin, Korea, with different land-use patterns, in order to enhance the effectiveness of water resource management strategies. Ten watersheds were classified into three land-use patterns (forest, agriculture and urban) using satellite images and geographic information system techniques, and in-situ denitrification rates were determined using an acetylene blocking method. Additionally, sediment samples were collected from each stream to analyze denitrifier communities and abundance using molecular approaches. In-situ denitrification rates were found to be in the order of agricultural streams (289.6 mg N20-N m-2 d-1) 〉 urban streams (157.0 mg N20-N m-2 d-1) 〉 forested streams (41.9 mg N20-N m-2 d-l). In contrast, the average quantity of denitrifying genes was the lowest in the urban streams. Genetic diversity of denitrifying genes was not affected by watershed land-use pattern, but exhibited stream-dependent pattern. More significance factors were involved in denitrification in the sites with higher denitrification rates. Multiple linear regression analysis revealed that clay, dissolved organic carbon and water contents were the main factors controlling denitrification rate in the agricultural streams, while dissolved organic carbon was the main controlling factor in the urban streams. In contrast, temperature appeared to be the main controlling factor in the forested streams.
基金supported by National Natural Science Foundation of China(Grant No.41371525)National Basic Research Program of China(Grant Nos.2012CB955800,2012CB955804)+1 种基金China Postdoctoral Science Foundation funded project(Grant Nos.2012M521390,2013T60696)Scientific Research Foundation for Returned Scholars(Grant Nos.2013(693),2013B065)
文摘Reducing Emissions from Deforestation and Forest Degradation(REDD+) and enhancing "removals of greenhouse gas emissions by forests" in developing countries through positive incentives is regarded as an essential component of the post-2012 climate regime for stabilizing greenhouse gas emissions and an important way of engaging developing countries in global mitigation efforts. We aimed to evaluate the potential effectiveness of REDD+ by integrating it into a land use option framework. One of our goals was to develop scenarios for evaluating the impacts of land use changes on carbon and environmental processes. In addition, we aimed to quantify the potential economic benefits to society of compensated reductions and to identify hotspots for applying REDD+. Three land use change scenarios were examined:(I) business as usual(BAU),(II) economic development, and(III) REDD+. A case study in Indonesia was examined using these land use scenarios and policy interventions, evaluating their effects on carbon emissions, socioeconomics, and environmental features of a spatial system using land use models. Significant emissions and water erosion reductions were predicted to be achieved under the REDD+ scenario, due to reduced deforestation of <6% over the next decade; >0.14 Mt CO2 e reduction was predicted relative to the BAU scenario. Furthermore, the spatial land use model indicated that REDD+ payments of forest carbon credits in the compliance market would play a key role in compensating rural communities and plantation companies for their opportunity cost in ending deforestation. This study provides an example of integrating land use modeling with a scenario analysis framework to evaluate plausible future forecasts and to evaluate the potential impacts of REDD+.
基金jointly supported by the National Natural Science Foundation of China(Grant Nos.41475083,41230422)the National Basic Research Program of China(Grant No.2011CB952000)the PriorityAcademic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Land use and land cover change(LUCC)is one of the important human forcing on climate.However,it is difficult to infer how LUCC will affect climate in the future from the effects of previous LUCC on regional climates in the past.Thus,based on the land cover data recommended by the Coupled Model Intercomparison Project Phase 5(CMIP5),a regional climate model(Reg CM4)was used to investigate the climate effects of future land use change over China.Two 15-year simulations(2036–2050),one with the current land use data and the other with future land cover scenario(2050)were conducted.It is noted that future LUCC in China is mainly characterized by the transition from the grassland to the forest.Results suggest that the magnitudes and ranges of the changes in temperature and precipitation caused by future LUCC show evident seasonality,which are more prominent in summer and autumn.Significant response of climate to future LUCC mainly happens in Northeast China,North China,the Hetao Area,Eastern Qinghai-Tibetan Plateau and South China.Further investigation shows that future LUCC can also produce significant impacts on the atmospheric circulation.LUCC results in abnormal southwesterly wind over extensive areas from the Indian peninsula to the coasts of the South China Sea and South China through the Bay of Bengal.Furthermore,Indian tropical southwest monsoons and South Sea southwest monsoons will both be strong,and the abnormal water vapor convergence from the South China Sea and the Indian Ocean will result in more precipitation in South China.